Fujitsu Corporation

Satoshi Shimokawa

Akiyoshi Uchida

Kiyoto Matsui

Masakazu Taguchi

Hiroyasu Kawano

Koichi Tezuka

Kazushi Uno

Hiroyasu Yoshikawa

Kazuyuki Ozaki

Yoshihiko Imanaka

Hirotaka Oshima

Haruhiko Izumi

Yuzuru Yamakage

Yasumasa Iwamura

Kyoko Tadaki

Goro Kawasaki

Shingo Hamaguchi

Kouichi Tezuka

Akihiko Makita

Tadashi Sato

Nobuyuki Kanto

Toshihisa Anazawa

An optimization calculation method includes: generating, by a computer, current generation individuals with a selected previous generation individual as a parent individual; evaluating each current generation individual by using a predetermined evaluation function; calculating a current generation constraint condition value based on a previous generation constraint condition value and a constraint condition provisional value which is achieved by more than half of the current generation individuals; determining whether a result of the evaluation for each current generation individual satisfies the current generation constraint condition value; determining a predetermined offset based on an attribute of each individual, which is generated by a mutation generating process, among individuals having the evaluation results satisfying the current generation constraint condition value; and adding the predetermined offset to a random number used to generate each next generation individual by the mutation generating process.

Optimization calculation method and information processing apparatus

An optimization calculation method includes, generating individuals of a present generation with an individual selected in a previous generation as a parent individual using an algorithm for obtaining optimum solutions while evolving a plurality of individuals for each generation, evaluating each individual of the present generation, setting a constraint condition value of the present generation based on a constraint condition value of one generation before with respect to the present generation, and a constraint condition provisional value achieved by a half or more of individuals used for generating child individuals of a next generation, determining whether an evaluation result of each individual satisfies a constraint condition value of the present generation, changing for lowering an evaluation result of individuals which do not satisfy the constraint condition value of the present generation, and selecting individuals to be solution candidates from among individuals on which the determination or change process is performed.

Optimization calculation method and optimization calculation apparatus

A power receiver includes: a secondary-side resonant coil that includes a resonant coil circuit and receives power from a primary-side resonant coil; a capacitor inserted into the resonant coil circuit; a series circuit including a first switch and a second switch; a first rectifying element having a first rectification direction; a second rectifying element having a second rectification direction; a detection circuit that detects a voltage or a current; a binarization processing circuit that outputs a rectangular wave obtained by binarizing the voltage or the current; a rectangular wave detection circuit that detects a rising or falling timing and a cycle of the rectangular wave; a reference clock generation circuit that generates a reference clock based on the rising or falling timing and the cycle; and a control circuit that generates a control clock used to switch on and off by adjusting a phase or a duty ratio.

Power receiver, power transmission system, and power receiving meihod

A power source includes a power source coil, a power transfer control unit, and a power receiver detection unit. The power source coil is configured to wirelessly transfer power to a power receiver using one of magnetic field resonance and electric field resonance, and the power transfer control unit is configured to control the power source coil. Further, the power receiver detection unit is configured to detect the power receiver by bringing the power receiver into proximity thereto or contact therewith.

Power source, wireless power transfer system, and positional information calculation method of power receiver

A power receiver includes a secondary-side resonance coil including a resonance coil part to receive power from a primary-side resonance coil by magnetic resonance; a capacitor in the resonance coil part of the secondary-side resonance coil; a series circuit of first and second switches connected in parallel with the capacitor; a first rectifier connected in parallel with the first switch, and having a first rectification direction; a second rectifier connected in parallel with the second switch, and having a second rectification direction opposite to the first rectification direction; a detector to detect a waveform of a power supply supplied to the secondary-side resonance coil; and a controller to adjust the waveform, and a phase difference between first and second signals to switch on and off the first and second switches, respectively, to adjust the power to be received by the secondary-side resonance coil.

Power receiver and power transmission system

A power receiver includes: a secondary-side resonant coil configured to receive electric power from a primary-side resonant coil through magnetic field resonance generated; a capacitor inserted in series in a resonant coil part of the secondary-side resonant coil; a series circuit, coupled in parallel with the capacitor, of a first switch and a second switch; a first rectifier coupled in parallel with the first switch, the first rectifier having a first rectification direction; a second rectifier coupled in parallel with the second switch and having a second rectification direction; a detector configured to detect the electric power received by the secondary-side resonant coil; and a controller configured to adjust phases of a first signal for switching on/off the first switch and of a second signal for switching on/off the second switch to adjust an amount of the electric power received by the secondary-side resonant coil.

Power receiver and power transmitting system

A power receiver includes: a secondary-side resonant coil including a resonant coil part to receive electric power from a primary-side resonant coil through magnetic field resonance; a first capacitor inserted in series in the resonant coil part; a series circuit of a first switch and a second switch; a first rectifier having a first rectification direction; a second rectifier having a second rectification direction opposite to the first rectification direction; a second capacitor inserted in series with the series circuit; a detector configured to detect a voltage waveform or a current waveform of the electric power; and a controller configured to adjust a phase difference between the waveform and a driving signal that includes a first signal for switching on/off the first switch and a second signal for switching on/off the second switch to adjust an amount of the electric power received by the secondary-side resonant coil.

A power transmitting apparatus includes a plurality of primary-side resonant coils disposed along a conveyance path of a plurality of electronic devices and configured to utilize magnetic field resonance to transmit electric power to secondary-side resonant coils of the respective electronic devices conveyed along the conveyance path; and a plurality of phase adjusters connected between an alternating-current source and the respective primary-side resonant coils and configured to respectively adjust phases of the electric power, supplied to the primary-side resonant coils from the alternating-current source, so as to uniform the phases of the electric power, supplied to the primary-side resonant coils from the alternating-current source.

Power transmitting apparatus

A power receiver includes: a secondary-side resonant coil including a resonant coil part to receive electric power from a primary-side resonant coil through magnetic field resonance; a capacitor inserted in series in the resonant coil part; a series circuit of a first switch and a second switch; a first rectifier having a first rectification direction; a second rectifier having a second rectification direction; a detector to detect a voltage waveform or a current waveform of the power; and a controller to adjust, in a state of adjusting a phase difference between the waveform and a driving signal that includes a first signal for switching on/off the first switch and a second signal for switching on/off the second switch to be a predetermined phase difference, a length of a period, during which the switches are both on, to adjust an amount of the power received by the secondary-side resonant coil.

A power receiver which wirelessly receives power from at least one power source using one of magnetic field resonance and electric field resonance, including a power receiver coil, an internal circuit, a power detection resistor, a switch, a power reception control unit, and a communication circuit unit. The power receiver coil wirelessly receives the power from the power source, and the internal circuit uses the power obtained by the power receiver coil. The power detection resistor detects the power obtained by the power receiver coil, and the switch applies a received power voltage obtained by the power receiver coil by switching to the power detection resistor. The power reception control unit controls the power detection resistor and the switch, and the communication circuit unit performs communication with the power source, comprising detection information of a received power and power supply timing information.

Power receiver, wireless power transfer system, and kQ-value calculation method

A rechargeable battery includes: a battery body including a cylindrical outer peripheral side surface; and a power receiving coil wound in at most a single layer around the outer peripheral side surface, and electrically connected to the battery body. The power receiving coil is helically wound around the outer peripheral side surface while forming a space from which the outer peripheral side surface is exposed.

Rechargeable battery, charging system, and electronic device

A power receiver includes: a first secondary-side resonant coil that receives electric power from a primary-side resonant coil through magnetic field resonance; a capacitor; a smoothing circuit; a pair of output terminals; a switch coupled in parallel to the capacitor or in series between a rectifier circuit and either a first terminal or a second terminal; and a drive controller that drives the switch through a first PWM drive pattern determined by a first duty cycle and by a first frequency that is less than or equal to a frequency of the magnetic field resonance. The first duty cycle is set based on a first efficiency of power reception of the first secondary-side resonant coil, a first rated output of a first load, a second efficiency of power reception of a second secondary-side resonant coil of another power receiver, and a second rated output of a second load.

A power transmission apparatus includes a primary coil connected to an AC source; a primary resonance coil configured to receive power from the primary coil; a secondary resonance coil configured to receive power from the primary resonance coil by magnetic field resonance occurred between the primary resonance coil and the secondary resonance coil; a secondary coil configured to receive power from the secondary resonance coil; a phase difference detector detect a phase difference between a phase of voltage supplied to the primary resonance coil and a phase of current flowing through the primary resonance coil; a variable capacitor provided on the primary resonance coil; and a determination part determining a coupling degree between the primary resonance coil and the secondary resonance coil based on a change degree of the phase difference relative to a change amount of capacitance when the capacitance of the variable capacitor changes.

Power transmission apparatus and power transmission method

A wireless power transfer system includes a plurality of power sources and at least one power receiver, in which power transfer from the power sources to the power receiver is performed in wireless by using magnetic field resonance or electric field resonance. In the system, one of the plurality of power sources is designated as a master power source and the other one or more power sources are designated as slave power sources. In addition, the master power source controls the plurality of power sources and the at least one power receiver to perform the power transfer. This allows the system to perform the power transfer in an optimum state.

Wireless power transmission system and wireless power transmission method

A power reception apparatus includes a plurality of power extraction coils that extract power from a coil being a power supply source, a switch that selects one of the plurality of the power extraction coils and connects the selected power extraction coil to a battery, and a controller that senses a charging state of the battery and changes over the switch. The plurality of the power extraction coils are different from each other in terms of a diameter, the number of turns, or a distance from the coil being the power supply source.

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Kawasaki, Japan

Satoshi Shimokawa